Control mechanism for laundry marking machines



P 1949- w. J. KEUPER CONTROL MECHANISM FOR LAUNDRY MARKING MACHINES 3 Sheets-Sheet 1 Filed July 7, 1944 zjwuwvfop WILLLQM .J. KJE PER P 20, 1949- w. J. KEUPER CONTROL MECHANISM FOR LAUNDRY MARKING MACHINES Filed July '7, 1944 3 Sheets-Sheet 2 W R E W P 3 U E K J m L L m mflfiu Hm vm mm ww wm O0 CCF Jew mm m0 3 G 8 mm d .K m @mw m mm Sept. 20, 1949. w. J. KEUPER 2,482,420

CONTROL MECHANISM FOR LAUNDRY MARKING MACHINES Filed July 7, 1944 3 Sheets-Sheet 3 sjwuq/rvfo o I WILLIAM axiu m Patented Sept. 20, 1949 CONTROL MECHANISM FOR LAUNDRY MARKING MAGHINES l iam hn C innati Ohi sisnor to The NationalMa -king Machine Company, Cincinnati, Ohio, a corporation of; Ohio Application July 7, 1944, Serial'No. 543,836

1'7 Claims. 1

My. invention relates to a new and improved control mechanism for laundry marking machine and has to do, more particularly, with a means for controlling a laundry marking machine with reference to alaundry. listing machine used there with.

In most modern laundries, it is customary t use a laundry marking machine to print, on each piece or article contained in a customers bundle, the laundry mark that has been assigned to that customer. When the bundle is opened, the operator first sets up on the marking machine the assigned laundry mark, by adjustment of the type-carriers, and places the successive articles of the bundle on the platen of the machine, op-. erating the machine each time to force the platen carrying the article against the type setup, to print the. assigned mark thereon. The approved practice. is to operate a laundry listing machine alongside the marking machine. When the operator opens the customers bundle, she takes out the list with the assigned laundry mark on it and places this list on the printing table of the listing machine. As already stated, she sets up this mark on the marking machine. The operator takes the first article from the bundle and depresses the key of the listing machine corresponding to the description of said article. If it is a sheet, she depresses the key labeled Sheets, if a towel, the key labeled Towels, and so on. She then marks the article with the assigned mark, on the marking machine, and then throws the piece into a truck or on a conveyor to be carried away for laundering. Ihis procedure is repeated for each article in the bundle. After the last article has been marked and listed, the operator prints the laundry list showing the number-cf articles of each classification by pulling up on the printing handle of the listing machine. This looks all the keys of the listing machine so that no more articles can be listed without previously resetting the machine to zero. The operator repeats this procedure with a new bundle, first resetting the listing machine to zero and setting up a new mark on the marking machine.

The principal object of my invention is to provide means which will call the operators attention to the fact that it is necessary to change the mark set-up of the marking machine at the conclusion of the list printing operation.

A further object of my invention is to provide an interlocking control between the marking machine and the listing machine of such nature that the printing of the list by the listing machine will disable themarking machine for subsequent marking operations, until enabled by certain manipulations of the operator.

Another object of my invention is to provide a control of alaundry marking machine suchthat the printing of the laundry list by the associated laundry listing machine will prevent subsequent marking operations of the marking machine until said control is automaticallyreleased by changing the mark set-up of said machine.

Still another object of my invention is to provide means actuated by the laundry listing machine, in the list-printing operation, for energizing a signal which directs the operators attention to the need for changing the mark set-up for the marking machine, and means for automatically deenergizing said signal by changing said mark set-up.

Further objects, and objects relating to details of construction and economies of operation, will definitely appear from the detaileddescription to follow. In one instance, I have accomplished the objects of my invention by the devices and means set forth in the following specification. My in; vention is clearly defined and pointed out in the appended claims. A structure constituting a preferred embodiment of my invention is illustrated in the accompanying drawings, forming a part of this specification, in which:

Fig. l is a diagrammatic view showing the electric circuits of my marking machine control,

Fig. 2 is a vertical, central View through a portion of the laundry marking machine, showing the location of the signal and of the photo-electric cell, with reference to parts of said machine.

Fig. 3 is a perspective view of portions of the marking machine, showing the location of the light source and the photo-electric cell, and the path of thelight beam.

Fig. 4 is a View, in front elevation, of the upper portion of the marking machine, showing the location of the signal.

Fig. 5 is a view, in sideelevation, of the laundry listing machine, showing the parts added thereto for controlling the marking machine, and

Fig. 6 is. a wiring diagram illustrating a modified form of controlling circuit.

In the drawings, the same reference numerals refer to the same parts throughout theseveral views.

In general, my invention consists in providing means, actuated by the operation of printing a laundry list on a laundry listing machine, for. disabling an associated laundry marking machine forsubsequent marking operations, and means for enabling said machine to permit fur-.-

ther marking operations. The enabling means may be actuated automatically by the adjustment of the marking machine type-carriers to set up a new mark. The marking machine may be of a type in which the marking operation is effected by application of fluid pressure to move a platen, on which the article to be marked is held, toward the type set at the printing line. In such case, the control may be effected by opening and closing a circuit connecting a source of electric current with the solenoid of an electro-magnetic valve in the line which supplies fluid pressure for operating the marking machine platen. Such circuit may be controlled by an electromagnetic relay having a holding circuit including a switch opened by the listing machine, when it is operated to print a list. This will break the holding circuit, allowing the relay to open and deenergize the valve solenoid so that the valve closes and cuts off the supply of fluid pressure for the marking machine platen. The relay may be closed, and the holding circuit reestablished, when the listing machine is in normal condition, by closing a circuit through the operating solenoid of the relay. This may be done manually by the operator, as by closing a pushbutton switch, or automatically as an incident to changing the mark set-up of the marking machine. One means of accomplishing this automatically may comprise a light source so located as to direct a light beam along a path between teeth of certain intermediate gears of the marking machine, when the type-carriers are aligned with selected type at printing position to print an assigned mark, and a photo-electric cell, on which said beam may impinge when the gears and type-carriers are aligned. This photo-electric cell, when active, generates an electric current which is delivered to the grid of an electronic amplifier, preventing the flow of current therethrough. Adjustment of any of the typecarriers, in setting up a new mark, will move one of the gears to interrupt the light beam and thus permit the passage of electric current through the amplifier to close the relay and reestablish the holding circuit therefor, permitting further marking operations at the will of the operator. The relay may also control a signal circuit indicating to the operator that it is time to change the mark set-up.

Referring to the numbered parts of the accompanying drawings, I have shown a laundry marking machine having a plurality of adjustable type-carriers or type-carrying wheels [0, with printing type on the peripheries thereof. Each of these wheels has a gear I I fixed thereto, which meshes with an intermediate gear [2. Each gear I2 meshes with a gear [3 fixed to the side of the corresponding indicating and setting wheel 14, having characters on the periphery thereof which correspond to the type on the type-carrying wheel 10. When the indicating wheels M are adjusted by the operator so that the characters forming an assigned laundry mark are visible through the opening of the sighting bar 15, corresponding type will have been brought to the printing line to print the assigned mark. An aligning bar I6 is provided, engaging between teeth of gears l2 and operated by the aligning device indicated generally at 11. The operator can throw the aligning bar [6 from effective to ineffective position, and vice versa, by the handle l8. The marking machine mechanism above described is substantially that shown in my pending application for United states Letters Patent on Laundry marking machine, Serial No. 529,882, filed April 5, 1944, now Patent Number 2,443,426, issued June 15, 1948.

This laundry marking machine may be of the sort having a. platen, on which the article of laundry to be marked is held, mounted in a platen-carrier rockable from normal to printing position and having a cylinder adapted to be connected with a source of fluid pressure. The platen is fixed to a piston working in said cylinder and, when the fluid pressure is admitted to the cylinder, the platen is moved toward the selected type, against the pressure of a spring, to print the mark on the article held on the platen. Such a platen-operating mechanism, generally, is shown in my pending application for United States Letters Patent for Laundry marking machine, Serial No. 470,052, filed December 24, 1942, now Patent Number 2,384,034, patented February 22, 1945. In Fig. l, I have shown diagrammatically the platen at IS, the cylinder at 22, the piston at 2|, the piston rod connecting the piston to the platen at 20, and the spring at 23. The means for controlling the admission of fluid pressure to the cylinder are not the same as in my said application, Serial No. 470,052, but include a conduit 24 leading to the cylinder and having therein an electro-magnetic valve 25 operated by solenoid 38. When the solenoid 38 is energized, valve 25 connects conduit 24 with tube 26 leading to a source of fluid pressure and disconnects it from exhaust pipe 21. When solenoid 38 is deenergized, valve 25 connects conduit 24 to exhaust passage 2! and disconnects it from the tube 26 leading to the source of fluid pressure. The circuit of the solenoid 38 includes certain switches, one closed by movement of the platen-carrier to printing position, and others closed by the hands of the operator as she holds the article on the platen.

In Fig. 5 I have shown, in side elevation, indicated generally at 28, a laundry listing machine of the type referred to above, which is used to control the laundry marking machine. This machine may be of the type shown in United States Letters Patent of George H. Lang, Nos. 1,352,070 and 2,119,713, to which cross-reference is hereby made. It includes a printing handle 29, which is rocked upwardly by the operator to carry the laundry list against the type in order to print the list. I have provided a cam 30 integral with the handle 29, adjacent the axis thereof, which engages a roller 3| carried by a stem 32 secured to a switch member 33. This switch member is normally held in closed position by the spring 34, but, when the printing handle 29 is rocked upwardly to print the list, the cam 30 presses the switch member 33 downwardly to open position against the pressure of spring 34.

Referring to Fig. 1, the power supply lines 35 and 36 are connected to a suitable source of electric current, such as a source of 110 volt, alternating current. Lead 31 connects line 35 to one end of the solenoid 38. The other end of solenoid 38 is connected by lead 39 to a switch 40. This switch is normally open but is closed by the movement of the marking machine platencarrier to printing position. The contact with which switch 40 cooperates is connected by lead 4| to a contact for a switch 42, the latter being connected by lead 43 to another switch 44. Switches 42 and 44 are normally open, but are held closed by the operator as she holds the article to be marked on the platen of the laundry marking machine. To this end, it is contemst nt. c lead; 45; to sw tch, :1 i

whe swi ches 4'1 4D 2 a scl qi tiw l e e e s pr, t, pl e ainoyczitandltheiart cl ihsld th 1 la pa o; r n a ma son switch 41- SaQlifill-JP negate V which: isrc n sizb eadtfl o, he; amp of a si nal 52am the lit conta it Qib e m heme 91 Ar n't t: an; sa es on ac, irc i .irQm ine 35 thronsh 1. V ea 59$, t tactta, swit h memb r: .1 and. ead; to. line 31 As shown in Fig. 2, the lamp 51 is located within amasingor housing 53 having a glass front 54, 01 which a suitahle-legend, such as Change mark? s, pl c d; h s signal casing s, pre alply rnounted on the front of the marking machine justq h elow the indicating andsetting wheels i4; shown-t n sst. nrl e th na circuit; is closed, it causes the legend to be ilmarinat d t sdi ect ns th operators attention to the fact that it is time to change the mark setp. f he laundry mark n ac e Sw tchm mb M f he 1ec rQ- as eticre laya operated b t so e id 59 a he op rating stem or armature 55 of saiolrelay is connested n an t e t h me b 5 wh ch conrai a h ldin ci uitw r 0 n cla 9, hen ol oid 1 ner d wi c ember 55 en: gages contact 5-1; and, when the solenoidis deenergized, it engages an idle contact 58. One ild- Q solenoid 59. is connectedby lead 60, to contact 61, with which the switch 33 coacts, The other contact 62 for the switch 33; is connected byleadt; to one end of the secondary 6,4, ofa transformer. The other end of said secondary isconnec ed by the lead, to the contact 5 1; The; primary 65 of saidtransformer is connected across the lines 35 and 35. The switch 33 is the one previously referred to, which is normally, closed'hy the spring 34 but opened by the movement of the printing handle 29 of the laundry listing machine, in printing a list. When solenoid 59 is energized, switch member 56, engaging contact 5:1; closes a holding circuit for said solenoid which includes the. transformer secondary 64, lead 63, switch member 33, lead 59, solenoid 59, leadSfl to thejunction point 9|, lead -92 to the switch member 55, contact 5'! and lead 66"00 the otherside of the transformer secondary-J So long as switch 33 and switch 55 remain closed, the holding circuit will be maintained, but the opening of switch 33 by the operation of printing a liston the listing machine breaks thisholding circuit; A condenser 68 is connected in parallel to-sw-itch 33 and 'solenoid 59 by leads and 69.

Anelectric lamp M constituting a light source is connected by lead i tov a point midwayuof transformer secondary 64, and by a lead 12. to thelead fificonnectedto one end of said second- As, showninEigl 3 thislight source IQ, is;

3, s.n: u ;tfid,, c mar n m thinain h thoi aid lis tb which will be interrupted by any movement of n of the termerlia s ars ziromap i of i nm nt. uch llv n c ssar lathe j m nt of. l? tre arn rs t se unanew mark The r st ,npoi Q1, wh hcis onnected by ad-B ome; and h i noiylfifi is co nectedloy lead T3 ,toltheanode-lt of an electr tub lfa h s ma-Qt e Thy a ro ty e, The cathode 16 of this electronic-tube is connected by. lead ilto leadlii, which connects to cne e- OI the transformer secondary 5,53. The grid 'la of h lfit rq ic hats n s-tee b had 19 ,1 9 he iisht ac f Qmie t 9 26 t ism h h or ectr a i; 8%, rite he a r. n tential et A 73 of the elect onic; tufce, which; supp: pa sa err a et e am efM- 1B, b itir s as e; l e i b a s rus d s it i l be i ter adiustm it r ed ate ea n et n una ewl l thesuppressing-pote ialgisreduced or,eli nd urr n n, l asev ,fome mns o m ondary 6,4 throughthe -lcad,G5 ,lead;H, ca t, an de Ml QW l El), switch 33 whicnwill new heciosed, lea

and'back tothe transfo ri-nersecondary 55. This ne izes. t e eno d: 53;, l s h sw hss 5,6 and dhand the-closing of switchfiii re h ish se. ho d as cuit hro gh. h olenoid 59, previously scribed. I s

e r l cond t o t h ir uit ll'b as shown inFig 1,,with solenoid till energizedwand the switches 5.6,and 4.! closed. Switch 33-is closed; because the'printing handle of thelaundry list-. ingmachine isinnormalposition, and thesolenoid 38:o f electroemagnetic valve 25 willbe-enep, gizediwhenever switches 41], 4,2 and; 44' are-closed, to permit the fluid-pressure comingfrorn pipe 25 to operate piston 2| for platen l9 and print a marl;v on an articleheld onthe platen. However, when-the Operator raises the printing handle Z-Q; of. the, listing machine toprint the laundry list, the switch 33 will be opened and this breaks-the holding circuit,for-solenoid 59-of,the electro-mag-.

netic relay and causes-switchmember- 4'! to move from contact 46to contact; 49, thus breaking the, circuit, including the solenoid 38 and closing the circuittoithesignal 51. As long as this condition exists, the electroemagnetic valve 25' cannot be opened to permit fluid pressure to flow to'the cyl-' inder- 22 to operatetheplaten of the marking mae chine, and the signal light5| will be energized to directthe operators'attention to the fact that the mark should-be changedi Whenthe operator fi nishes theprinting of the laundry list, handleZB. returns to normal position and-switch 33 will be closed by the spring, but this will be ineffective, lay-itself, toenergize solenoid 59 and reestablish the holdingcircuit. However, just as soon as the operator adjusts any of the type-carriers IQ, the movement of one or moreof intermediate gears l2 williinterrupt the light beam from source 10; andpermittcurrentto pass through the electronic tube 1,5,whi-ch, since s,witch;33 is closed, will enrsize q noid .fir walls; witshms bersvti .nst

56 on contacts 46 and 51, and thus reestablishing the holding circuit for solenoid 59. The platen will be operated, to print a mark on an article held thereon, whenever the switches 49, 42 and 44 are closed, until the handle 29 of the laundry listing machine is again raised to open switch 33, in the operation of printing a new list. The signal light will be deenergized as soon as switch member 41 is moved from contact 49 to contact 46.

In Fig. 6, I have shown a modified form of my invention, in which the transformer, 64, 65, the electronic tube 75, the light source and the photo-electric cell 80 are eliminated, and solenoid 59 is energized, and the holding circuit therefor reestablished, by the operators closing a pushbutton switch, when the switch 33 is closed due to the return of the printing handle 29 to normal position. Contact 62, with which switch 33 cooperates, is connected by leads 63, 82 and 8 l to the handle 29 of the laundry listing machine is moved upwardly to print the list, and the movement of switch member 56 from contact 51 will open the holding circuit for said solenoid 59. To energize solenoid 59 and reestablish the holding circuit therefor, the operator closes the push-button switch 81, so that the circuit is completed from the power line 35 through lead 83, contact 84, switch 81, contact 85, leads 86 and 90, solenoid 59, lead 60, contact 6i, closed switch 33, contact 62, lead 63, and leads 82 and 8| to the power line 36. This causes the switch member 56 to engage contact 51, which completes the holding circuit for solenoid 59 from the power line 35 through contact 51, switch member 56, leads 92 and 99, solenoid 59 and back to the power line 36. With this modified form of control, the circuitto solenoid 38 will be broken at the switch 4'! when the handle 29 of the laundry listing machine is raised to print the laundry list. The laundry marking machine is then disabled for subsequent marking operations, until switch 41 is again closed. At the same time, the circuit to the signal light 5| is energized and that signal is illuminated to indicate to the operator that it is necessary to change marks. The marking machine can be enabled for subsequent marking operations, after handle 29 of the listing machine has been returned to normal and switch 33 has been closed, by closing the push-button switch 81 temporarily, which will energize solenoid 59 and, by closing switch 56 on contact 51, reestablish the holding circuit for said solenoid.

I am aware that the marking machine control shown herein may be varied considerably without departing from the spirit of my invention and, therefore, I claim my invention broadly, as indicated by the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is: V

1. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine, of means, actuated by said listing machine in the operation of printing a list thereby, for disabling 8 said marking machine for subsequent marking operations; and means efiective only while the listing machine is in non-printing condition for enabling said marking machine to permit subsequent marking operations thereby.

2. A mechanism of the class described comprising the combination with a laundry listing machine of a signal device; operating means therefor; means controlled by said listing machine for automatically actuating said operating means upon the printing of a list by said listing machine; and operable means for disabling said operating means, efiective upon return of said listing machine to normal after printing said list.

3. A control for laundry marking machines comprising the combination with a laundry marking machine and a laundry listing machine of a signal device; means, actuated by said listing machine in the operation of printing a list thereby, for operating said signal device and disabling said marking machine for subsequent marking operations; and operable means, effective only when said listing machine has been normalized after printing a list, for causing said signal device to cease operation and enabling said marking machine.

4. A control for laundry marking machines comprising the combination with a laundry marking machine and a laundry listing machine having a printing handle movable from normal to printing position to print a laundry list, of a signal device; means, actuated by movement of the listing machine handle to printing position, for operating said signal device and disabling said marking machine for subsequent marking operations; and operable means, effective only when said handle is in normal position, for causing said signal device to cease operation and enabling said marking machine.

5. A control for laundry marking machines comprising the combination with a laundry marking machine, having fluid pressure means for moving a platen toward type to print a mark, and a laundry listing machine, of an electro-mag 7 netic valve controlling admission of fluid pressure to said platen-moving means; an electric circuit in which said electro-magnetic valve is connected; a switch for opening and closing said circuit; movable means, moved from normal position by said listing machine during part of the operation of printing a list thereby and thereafter returned to normal position, for moving said switch to open position to thereby disable said marking machine and means rendered operable when said movable means is in normal position for moving said switch to closed position to enable the marking machine.

6. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having fluid pressure means for moving a platen toward type to print a mark, of an electro-magnetic valve controlling admission of fluid pressure to said means; a circuit connecting said electro-magnetic valve with a source of electric current; an electromagnetic relay in said circuit; means, actuated by said listing machine in the operation of printing a list thereby, for operating said relay to break said circuit; and means, effective only when said listing machine is normalized, for operating said relay to reestablish said circuit.

7. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having an element adjustable to condition the operation of printing a list thereby, for disabling said marking machine for subsequent marking operations; and means, actuated by movement of said element away from its last adjustment while the: listing-=machine is in non-printing condition for'enabling said marking machine for subsequent operation.

8: A\ control for laundry marking machines comprisingv the combination with a laundry listing machine and a laundry marking machine having an element adjustable to condition the marking machine to print different marksof a signal device; means, actuated by said listing machine in. the operation of printing a listthereby,.for'operating said signal device; and operable means, actuated by adjustment of said element for: causing. said signal device to cease operation.

9. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having an element adjustable to condition the marking machine to print different marks of a signal device; means actuated by said listing machine in the operation of printing a list thereby, for operating said signal device and disabling said marking machine for subsequent marking operations; and operable means, actuated by movement of said element from its last adjustment while said listing machine is in non-printing condition for causing said signal device to cease operation and enabling said marking machine.

10. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable type-carriers, of means, actuated by said listing machine in the operation of printing a list thereby, for disabling said marking machine for subsequent marking operations, and means, actuated by adjustment of any of said typecarriers while said listing machine is in nonprinting condition, for enabling said marking machine for subsequent marking operations.

11. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable type-carriers, of a signal device; means, actuated by said listing machine in the operation of printing a list thereby, for operating said signal device; and means, actuated by adjustment of any of said type-carriers while said listing machine is in nonprinting condition, for causing said signal device to cease operation.

12. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable type-carriers, of a signal; means, actuated by said listing machine in the operation of printing a list thereby, for energizing said signal and disabling said marking machine for subsequent marking operations; and means, actuated by adjustment of any of said type-carriers while the listing machine is in nonprinting condition, for deenergizing said signal and enabling said marking machine for subsequent marking operations.

13. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable toothed members, of means, actuated by said listing machine in the operation of printing a list thereby, for disabling said marking machine for subsequent marking operations; and'means for enabling saidmarking machine for subsequent marking operations ineluding a lightsource arranged to project a light" beam between the. teeth of said toothed members when they are aligned, and a photo-electric cell" disposed to receive said beam, said beam being interrupted by adjustment ofany of said toothed" valve controlling admission of fluid pressure to:

said means; a circuit connecting said electromagnetic valve with asource of electric current; means, actuated by 'saidlisting machine in the operation of printing a list thereby, for opening said circuit; and means, actuated by adjustment of any of said type-carriers while said listing machine is in non-printing condition, for closing said circuit.

15. A control for laundry marking machines comprising the combination of a laundry listing machine and a laundry marking machine having fluid pressure means for moving a platen toward type to print a mark on an article held on the platen, of an electro-magnetic valve controlling the admission of fluid pressure to said platenmoving means; an electric circuit for said electromagnetic valve including a relay having an operating solenoid; a holding circuit for said operating solenoid; a normally-closed switch in said holding circuit; means, actuated by said listing machine in the operation of printing a list thereby, for opening said normally-closed switch; and means operable when said normally-closed switch is closed for energizing said solenoid and reestablishing said holding circuit.

16. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable type-carriers and fluid pressure means for moving a platen toward said type-carriers to print a mark upon an article held on said platen, of an electro-magnetic valve controlling admission of fluid pressure to said platen-moving means; an electric circuit including said electro-magnetic valve; a relay in said circuit and having an operating solenoid; a holding circuit for said solenoid; a normally-closed switch in said holding circuit; means, actuated by said listing machine in the operation of printing a list, for opening said normally-closed switch; a light source projecting a light beam in such a path that it will be interrupted by adjustment of any of said type-carriers from printing position; a photo-electric cell upon which said light beam impinges when uninterrupted; and means operable when said normally-closed switch is closed, and controlled by said photo-electric cell, for energizing said operating solenoid and reestablishing the holding circuit therefor,

1'7. A control for laundry marking machines comprising the combination with a laundry listing machine and a laundry marking machine having a plurality of adjustable type-carriers and fluid pressure means for moving a platen toward said type-carriers to print a mark on an article held on the platen, of an electro-magnetic valve controlling the admission of fluid pressure to said 11 platen-moving means; an electric circuit including said electro-magnetic valve; a relay included in said circuit and having an operating solenoid; a holding circuit for said operating solenoid; a normally-closed switch in said holding circuit; means, actuated by said listing machine in the operation of printing a list, for opening said normally-closed switch; an energizing circuit for said operating solenoid including said normally-closed switch and an electronic tube; a photo-electric cell connected to the grid of said electronic tube; and a light source arranged to project a light beam upon said photo-electric cell when the adjustable type-carriers are aligned at printing position and interrupted by any adjustment of any of said type-carriers from printing position, the interruption of said light beam by such adjustment permitting the passage of electric current through said solenoid-energized circuit, when said normally-closed switch is closed.

WILLIAM JOHN KEUPER.

12 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Certificate of Correction Patent N 0. 2,482,420 September 20, 1949 WILLIAM JOHN KEUPER It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Column 4, line 19, for Patent Number 2,384,034 read Patent Number 2,384,085

line,20, for February22, 1945 read September 4, 1945; column 11, line 19, for the word energized read energizing;

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 24th day of January, A. D. 1950.

THOMAS F. MURPHY,

Assistant Uommiasz'oner of Patents.

Certificate of Correction Patent N 0. 2,482,420 September 20, 1949 WILLIAM JOHNKEUPER It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Column 4, line 19, for Patent Number 2,384,034 read Patent Number 2,384,035

-line 20, for February 22, 1945 read September 4, 1945; column 11, line 19, for the word energized read energizing;

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 24th day of January, A. D. 1950.

THOMAS F. MURPHY,

Assz'atamt Oommz'ssioner of Patents. 

